Atwood Machine and the Work done

[animesh27194]

The two block in an atwood machine have masses 2kg and 3kg. Find the work done by gravity during the fourth second after the system is released from rest.I have attached my attempt here..Kindly tell me where I went wrong.
I am sure that I didnt go anywhere wrong in finding the acceleration and the displacement. But, I am doubtful abt the work done part. The answer is coming out to be 67 joules.

 

[Doc Al]

Find the work done by gravity during the fourth second after the system is released from rest.

What's the displacement during the fourth second? (That's from t₁ = 3 s to t₂ = 4 s.)

Also realize that one mass moves up while the other moves down, so the work done on each will have a different sign. Presumably, you want the net work done?

 

[animesh27194]

ooooh! I am so sorry...! THat's a silly mistake..! :P

 

[Doc Al]

See also the comment I added to my last post.

 

[animesh27194]

THanks a lot! I understood the concept... :)